Volkswagen AG executive Oliver Schmidt pleaded guilty on Friday in US District Court in Detroit in connection with a massive diesel emissions scandalthat has cost the German automaker as much as $25 billion.

Representational image. Reuters

Under a plea agreement, Schmidt faces up to seven years in prison and a fine of between $40,000 and $400,000 after admitting to conspiring to mislead US regulators and violating clean air laws. He will be sentenced on 6 December.

In March, Volkswagen pleaded guilty to three felony counts under a plea agreement to resolve US charges it installed secret software in vehicles to evade emissions tests.

US prosecutors have charged eight current and former Volkswagen executives.

Earlier this year, Schmidt was charged with 11 felony counts and federal prosecutors said he could have faced a maximum of up to 169 years in prison. As part of his guilty plea, prosecutors agreed to drop most of the counts.

Volkswagen said on Friday it "continues to cooperate with investigations by the Department of Justice into the conduct of individuals. It would not be appropriate to comment on any ongoing investigations or to discuss personnel matters."

As part of the agreement, Volkswagen has agreed to spend as much as $25 billion in the United States to resolve claims from owners and regulators over polluting diesel vehicles and offered to buy back about 500,000 vehicles.